Listeriosis (Listeria monocytogenes Infection) Facts

Listeriosis is a disease caused by infection with the bacterium Listeria monocytogenes, and it is most often contracted after eating contaminated foods or liquids.

Listeriosis most commonly affects newborns, the elderly, pregnant women, and those individuals with a poorly functioning immune system (immunocompromised).

Most healthy individuals who come in contact with Listeria monocytogenes will have either no symptoms or a self-limiting mild gastrointestinal illness.

In the United States, most cases occurr during the summer months.

The symptoms of listeriosis may include diarrhea, nausea, vomiting, fever, and muscle aches. More serious illness may lead to sepsis, meningitis, and death.

Listeriosis is diagnosed by culturing and isolating Listeria monocytogenes from stool, cerebrospinal fluid, blood, amniotic fluid, or the placenta. A presumptive diagnosis of listeriosis can be made based on the patient's symptoms in the setting of exposure to contaminated food during a listeriosis outbreak.

The treatment of listeriosis involves intravenous antibiotics and supportive care.

The prognosis for individuals with listeriosis depends on several factors. Though most cases carry an excellent prognosis, those patients with underlying risk factors and severe disease are at risk for significant morbidity and mortality.

Several measures can be taken to prevent infection with Listeria monocytogenes, including proper food handling and preparation, as well as the avoidance of certain high-risk foods and liquids.